Ajay Mohan

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Ajay Mohan

Sep 17, 2021 14:10

I see.. Thanks for your input. I'll consult some more before I make the decision.

Ajay Mohan

Sep 17, 2021 14:05

How much RAM did you purchase for your M1 air? 8 or 16 GB?

Ajay Mohan

Sep 17, 2021 14:04

I see..

even I'm making my decision upon the contingency that my university provides a linux system to fall back on, in case things dont work with mac.

Ajay Mohan

Sep 17, 2021 14:01

I see

Ajay Mohan

Sep 17, 2021 13:57

All that can be done on linux, can be done on mac too right?

Ajay Mohan

Sep 17, 2021 13:57

@Dan

Ajay Mohan

Sep 17, 2021 13:47

@Slereah Why is that so?

Ajay Mohan

Sep 17, 2021 13:47

@ACuriousMind They haven't given me a university computer yet but you're right, I also assume that I'll be doing all the serious work on the university computer.

Ajay Mohan

Sep 17, 2021 13:31

Any word of advice?

Ajay Mohan

Sep 17, 2021 13:31

Hello,

I'm a physics graduate student and I've decided to buy a macbook. I'm planning to specialize in lattice QCD (which is mostly done on python). Is M1 Macbook Air sufficient or do I need to go for Pro (because of the fan inside)?

Ajay Mohan

Feb 7, 2021 20:17

Anyone know what's the meaning of the word "virial" in the virial expansion of classical interacting gas for e.g.?

Ajay Mohan

Apr 28, 2020 06:23

Asking for their personal details (such as email-ID) on comments is forbidden according to SE rules.

Ajay Mohan

Apr 28, 2020 06:22

Also, most of the time, the names of SE users are random. The user who answered my question is "DinosaurEgg"

I would like to cite their answer using their real name if possible.

Ajay Mohan

Apr 28, 2020 06:17

Yes, I saw that option. But, how can one get rid of the above drawback?

Ajay Mohan

Apr 28, 2020 06:16

One of the biggest drawback of citing SE answers (apart from the authenticity of SE answers): Since answers in SE can be modified over time, I don't think it would provide an accurate reference.

Ajay Mohan

Apr 28, 2020 06:09

Hey guys, quick question.
A few days back, I asked a question on Math.SE with the goal of getting a slight hint that would let me solve a mathematical calculation I have been assigned to do by my thesis advisor. This calculation will be published in a peer-reviewed paper that I'm writing with my thesis advisor.
But, instead, a user gave the full solution as the answer. Not his mistake, as the full solution was just a few steps away from the hint.

My question is: How do I cite the user's answer on Math.SE on my paper? Is it a common practice?

Ajay Mohan

Feb 18, 2020 09:34

@Slereah Hmm. I feel I don't have the necessary prerequisites to even understand most research problems. And now I'm being asked to pick problems that I would like to work on... Most probably it just reflects my poor preparation during my undergraduate study.

Ajay Mohan

Feb 18, 2020 09:28

(1) is reasonable. But is it reasonable to expect (2) and (3) from an incoming PhD student

Ajay Mohan

Feb 18, 2020 09:27

I'm applying for a graduate school which asks the PhD candidates to submit a statement of interest that address the following questions in particular: (1) your area of interest ? (2) specific problems you would like to work on? (3) can you suggest some methods to deal with such problems? [This note is written beside it: The write-up should reflect original ideas. Don't write a general essay describing the area]

Ajay Mohan

Feb 18, 2020 09:21

The major obstacle I feel is that it takes a lot of prerequisites (like general relativity, quantum field theory, string theory) to even understand the research problems in this field: Without these prerequisites, it's extremely hard to understand the research papers in this field. And these prerequisites are generally taught in the beginning of a typical graduate program.

Ajay Mohan

Feb 18, 2020 09:21

How knowledgeable should an incoming PhD student in the field of high energy theory be?

Ajay Mohan

Feb 4, 2020 13:21

The only reason I can think of is time. Maybe they don't want to put too much time on teaching as even teaching "satisfactorily" requires a good deal of preparation.

Ajay Mohan

Feb 4, 2020 13:17

I'm unable to completely grasp the statement because I'm unable to see what stops someone who has good knowledge of a particular field from being a good teacher. What else does one need to teach "satisfactorily"?

Ajay Mohan

Feb 4, 2020 13:15

This is a common sentiment shared by many and I've heard people pick examples of teachers that they have encountered during their academic career who fit this profile: They describe someone who has a very good research profile but is absolutely bad at teaching.

Ajay Mohan

Feb 4, 2020 13:15

How can I better understand this statement: A person who has a good understanding of a particular field of study need not necessarily be good at teaching in the said field. By "good at teaching", I mean "a satisfactory level of teaching as experienced by the students."

Ajay Mohan

Dec 13, 2019 13:53

Hey guys. I would be deeply grateful if someone could mention various active research topic/areas that are currently pursued using AdS/CFT?

Ajay Mohan

Dec 11, 2019 21:14

You too.

Ajay Mohan

Dec 11, 2019 21:10

If the agent is applying force in such a way that the initial and final KE is the same (or $\Delta KE=0$), then this equation is valid. You can once again see this from the work energy theorem : $W_{agent} + W_{conservative force} = \Delta KE = 0 \Rightarrow W_{agent} = - W_{conservative force} = \Delta PE$.

Ajay Mohan

Dec 11, 2019 21:05

I'm here. Go on.

Ajay Mohan

Dec 11, 2019 20:51

It's no problem. Best of luck.

Ajay Mohan

Dec 11, 2019 20:37

thumbs up emoji

Ajay Mohan

Dec 11, 2019 20:36

Sure, play with the idea. That's how it starts to "stick" in your mind.

Ajay Mohan

Dec 11, 2019 20:35

Yes, it's valid for any conservative force, including the spring force.

Ajay Mohan

Dec 11, 2019 20:33

Go ahead.

Ajay Mohan

Dec 11, 2019 20:32

No problem. It's great to see that my sleeplessness has come of some use.

Ajay Mohan

Dec 11, 2019 20:30

Yes, you've got it right.

Ajay Mohan

Dec 11, 2019 20:18

Yes, the negative of the change in potential energy is nothing but the work done by the conservative force.

Ajay Mohan

Dec 11, 2019 20:14

I would suggest you take this as the definition of potential energy: $U(r_{A})-U(r_{B})=W(A\to B)=\int_{A}^{B}\vec{F}_{\text{conservative force}}.d\vec{r}$. Note that A and B are switched in the LHS

Ajay Mohan

Dec 11, 2019 20:13

Ah, they haven't placed a negative sign. The $\mathbf{F}$ in this equation is the external applied force that is equal and opposite to the conservative force acting on the object.

Ajay Mohan

Dec 11, 2019 20:08

@MuhammedÇ.TUFAN I'll wait.

Ajay Mohan

Dec 11, 2019 20:07

(contd.) Now, we know that the work-energy theorem says that the work done by the net force acting on the object is equal to the change in kinetic energy of the object. In my case, it is only the conservative force acting on the object. Therefore, this implies : $W_{\text{by conservative force}} = -\Delta PE = \Delta KE \Rightarrow \Delta PE + \Delta KE = 0$.

Ajay Mohan

Dec 11, 2019 20:05

(contd.) So, $\Delta PE$ is just another way of writing the work done by the conservative force in the problem. But, here comes the twist in most textbooks : They define their potential energy as the negative of my potential energy. Therefore, if we choose that convention, $-\Delta PE$ is another way to write the work done by the conservative force.

$Mathematics$ Mathematics

Associated with Math.SE; for both general discussion & math qu...

Ajay Mohan

Apr 16, 2020 10:23

The usual way eq. 1 is proved is by using an infinitesimal gaussian pill-box. But, I wish to show eq. 1 from eq. 2.

Ajay Mohan

Apr 16, 2020 10:19

Ajay Mohan

Apr 16, 2020 10:19

I have a question and I would really appreciate any help/suggestions. I'll attach the screenshot of the problem below.

Problem Solving Strategies

General chat for high school physics. For MathJax see meta.sta...

Ajay Mohan

Jan 19, 2020 12:04

@JohnRennie Okay.. no problem.

Ajay Mohan

Jan 19, 2020 12:03

Equation (4) is just the familiar electrostatic boundary condition for the perpendicular component of the electric field (Equation (2.31) in (this)[i.sstatic.net/4Uc0w.png] image).

Ajay Mohan

Jan 19, 2020 11:52

Alright. Consider the problem of a general surface charge distribution $\sigma(\theta,\phi)$ on a sphere of radius $R$. I want to show that $\lim_{r \to R^+} \partial_r \Phi(r,\theta,\phi) - \lim_{r \to R^-} \partial_r \Phi(r,\theta,\phi) = - \frac{\sigma(\theta,\phi)}{\epsilon_0}$. This can be shown using an infinitesimal gaussian cylindrical surface covering the area of interest. But, I'm asked to show it using the Green's function solution for $\Phi$ (equation $(2)$ in the above picture).

Ajay Mohan

Jan 19, 2020 11:51

Ajay Mohan

Jan 19, 2020 11:42

I have a question, John. I'll ask after Aladdin's finished with his topic.